The present invention relates to a tamper evident cap. It finds particular application in conjunction with a valve outlet for a pressurized cylinder and will be described with particular reference thereto. It will be appreciated, however, that the cap is also suited to use with a variety of other fluid outlets.
Tanks filled with pressurized gases, such as refrigerants for use in cooling systems, are generally supplied with a valve for sealing an outlet from which the fluid is dispensed. Because of the high cost of certain gases, such as chlorofluorocarbons (CFCs), it is common to incorporate some type of tamper-evident feature after filling the tank with refrigerant, which provides an indication of whether the valve has been opened. In the event that a customer reports that the tank is empty or suffering a loss of contents, the tamper-evident feature allows a supplier to determine whether the valve is leaking or whether the valve has been opened.
One current method used by suppliers is to fit a water-based transparent shrink-wrap sleeve over the valve handle and valve body. The sleeve is applied wet, and shrinks on drying. Another method incorporates a heat-shrink type of sleeve. It has been found, however, that the sleeve may sometimes be taken off and replaced without providing evidence of tampering, for example, by soaking the sleeve. A customer or other person in the chain of supply can thus remove the sleeve, relieve the refrigerant and then replace the sleeve to defeat the tamper evident device. Additionally, the heat-shrink version can sometimes become brittle and crack even when not subjected to tampering and thus provide a false indication of tampering.
There remains a need for an improved tamper-evident device for providing an indication of whether a refrigerant tank has been at least partially emptied or otherwise tampered with. The present invention provides a new and improved tamper-evident valve outlet cap and method of use which overcomes the above-referenced problems and others.
In accordance with one aspect of the invention, a tamper-evident closure for an associated outlet is provided. The closure includes a cap which rotatably engages the outlet. A tamper evident ring is carried by the cap and has at least one projection, rotation of the cap in a cap removal direction being opposed by engagement of the at least one projection with a surface of the associated outlet until a portion of the ring or cap breaks, allowing the cap to be removed from the associated outlet.
In accordance with another aspect of the invention, a combination of closure assembly and an outlet is provided. The outlet has an internal bore with an opening for dispensing a fluid therefrom and a land on an exterior surface thereof. The closure assembly includes a cap configured for attachment to the outlet so as to cover the opening. A tamper-evident ring is operatively connected with the cap by at least one tab, the ring includes at least one projection for engaging the land on the outlet to resist removal of the cap from the outlet until movement of the cap in a cap removal direction breaks one or more of the tabs and/or projections.
In accordance with another aspect of the invention, a method of providing evidence of removal of a cap from an outlet is provided. The method includes rotatably engaging a cap with the outlet until at least one projection carried by the cap contacts a surface of the outlet. The projection resists rotation of the cap in a cap removal direction. The method further includes applying a sufficient force to the cap in the cap removal direction to cause a portion carried by the cap to break, allowing the cap to be removed from the outlet.
In accordance with another aspect of the invention, a tamper-evident closure for an outlet is provided. The closure includes a cap which rotatably engages the outlet. The cap includes a slot. The closure further includes a tamper evident ring including a tab and a projection. The tab includes a frangible portion and at least one finger that snap fits into the slot on the cap. Rotation of the cap in a cap removal direction is opposed by engagement of the projection with a surface of the outlet until the frangible portion of the tab breaks, allowing the cap to be removed from the outlet.
One aspect of the present invention is the provision of a tamper-evident closure for an outlet.
Another aspect of the present invention is the provision of a tamper-evident closure in which a tamper evident ring carried by a cap has at least one, and preferably a plurality of projections which oppose rotation of the cap until a portion of the ring breaks, providing evidence of tampering.
Still another aspect of the present invention is the provision of a tamper evident ring with at least one tab, and preferably a plurality of tabs, which snap fit into a slot or slots on the cap, the tabs breaking under applied rotational pressure as evidence that the closure has been removed.
Yet another aspect of the present invention is the provision of a tamper evident ring for a closure in which tabs on the ring each include a finger at a distal end thereof which passes through the slot on the cap to prevent removal the cap from the ring without breaking the tabs.
A further aspect of the present invention is the provision of a tamper-evident closure in which the tab or tabs extend from a first surface of an annular disk and the projection or projections extend from a second, opposite or side surface of the disk.
A still further aspect of the present invention is the provision of a tamper-evident closure in which the projections are formed from a cut-out portion of an annular disk.
A yet further aspect of the present invention is the provision of a tamper-evident closure in which projections on a tamper-evident ring each include a sliding portion and an engagement portion, allowing the closure to be rotatably engaged with an outlet by sliding of the sliding portions over a land, the engagement portions engaging the land when the closure is rotated in an opening direction.
A yet still further aspect of the present invention is the provision of a tamper-evident closure in which the engagement of tabs on a tamper-evident ring with the cap opposes rotation of the cap relative to the ring during rotation of the cap in the cap removal direction until a sufficient rotational force is applied to break the tabs.
A yet still further aspect of the present invention is the provision of a tamper-evident closure with a seal retained in a groove on an inner surface of the cap, the seal sealing the cap to the outlet.
Another aspect of the present invention is the provision of a closure assembly and an outlet, the closure including a tamper-evident ring operatively connected with a cap by at least one tab, the ring including a projection for engaging a land on the outlet to resist removal of the cap from the outlet until movement of the cap in a cap removal direction breaks the tab.
Yet another aspect of the present invention is the provision of a method of providing evidence of removal of a cap from an outlet.
Still other aspects of the present invention will become apparent to those skilled in the art upon a reading and understanding of the following detailed description.